Tow Vehicle Question

Going to retire soon and thinking about buy a travel trailer. While researching tow vehicles it has become a little overwhelming because they all seem to have some sort of reliability issues. All of the travel trailers we have looked at are 6k lbs or less. Which 1/2 ton pickup would you recommend as a reliable and comfortable tow vehicle. Would buy used and budget is about $50k or less.

ETA: received many suggestions for 3/4 ton. I want to be open minded, so which 3/4 tons do you suggest for comfort and reliability also?